A lil' Lost
 

I have a standard '02 Deville. The car had been cutting off on me and the check engine light was coming on and off so I took it to the local dealership and let
them do what they do and a few hours later they told me that it was the "crank shaft dispostion sensor" and that it would cost 460.00 to replace. I'm not cheap and I'm not lazy either. So if this is something simple ( b/c i know sensors are usually just plugged and mounted, but the hard part can be getting to them). So if anybody has any knowledge about these sensors and where they located could you please post on this. also if any knows a link to a diagram for the motor i would greatly appreciate it if you could post that too or refer me to a older post that has 1.
thanks in adance